I'm looking to do a 5 lug conversion on my '84 GSL. Currently I'm running 15 inch wheels with a 4x114.3 lug pattern. I'm interested in running the 5x114.3 lug pattern present on the GSL-SE. I was wondering if anyone here has done that, what you reckon the least painful method of achieving that is, and if you have any other advice that would've made your conversion easier. I've heard stories of people swapping their axles in order to achieve this, but I'm crossing my fingers that there's an easier way. Hopefully somebody here can shed some light on this; my end goal is to basically do an entire GSL-SE conversion on my car.

If you want to convert your GSL to 4x114.3, get wheel adaptors, or covert to GSL-SE front struts and brakes and rear axle and brakes. (lots of work if you goal is just to fit different wheels, not many advantages other than PCD)

If you want to covert to FC 5x114.3, get wheel adaptors, or convert to GSL-SE front struts, axle and brakes, and then find a RE Speed conversion kit to fit FC front hubs. I'm pretty sure to make this work you will also need to run FC discs and 4 pot callipers which needs a RE speed bracket to fit. On the rear you will need to use Moser Axles with 5x114.3 hub in the GSL-SE axle and this will allow you to run FC rear discs, and again you will need a RE speed bracket to use FC twin pot rear calipers. (Huge amount of work, but you will get better brakes which are an advantage on a track car with sticky rubber, but not required for even high powered NA street cars)

The main issue is the RE speed parts are no longer available so you will need to search for used items, and it will be hard to find the right parts, although I believe some parts have been copied and are being manufactured in China, I'm not sure where these can be bought from, try looking on eBay.